Knee protection apparatus for vehicle occupant

ABSTRACT

A knee protection apparatus includes an airbag and an airbag support that is attached to the airbag. Upon deployment of the airbag, the airbag support together expands so as to cover the instrument panel and thus help the airbag smoothly expand.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a vehicle occupant protectionapparatus, and more specifically, it relates to a knee protectionapparatus for a vehicle occupant, which protects the occupant's knees bydeploying an airbag stored in front of the knees using the gas from aninflator upon collision of the vehicle.

2. Description of the Related Art

A known protection apparatus of this kind (e.g., Japanese Laid-openPatent Application No. 2002-249016) includes an airbag that is providedwrapped in front of the knees of an occupant and, when supplied with gasfrom an inflator, develops along the surface of the instrument panel toexpand between the instrument panel and the occupant's knees.

However, there is only a small space allowed for such deployment of theairbag, namely between the instrument panel and the knees of theoccupant, and what is more, there are protrusions and indentations onthe instrument panel side, such as those formed to provide goodappearance of the instrument panel and formed by some related partsattached thereon, and it is therefore considered that the airbag wouldget caught on such protrusions and indentations when it expands asaforementioned.

SUMMARY OF THE INVENTION

The present invention has been made to provide a knee protectionapparatus for a vehicle occupant which solves the aforementionedproblem. A first aspect of the invention relates to a knee protectionapparatus for a vehicle occupant, including: an airbag that is disposedin front of a knee of the occupant; an inflator that supplies gas to theairbag upon collision of the vehicle so that the airbag is deployed bythe gas supplied; and an airbag support that expands upon deployment ofthe airbag so as to cover an instrument panel of the vehicle.

According to this construction, when the airbag is deployed by the gassupplied from the inflator, the airbag support covers protrusions andindentations on the surface of the instrument panel so that the airbagwould not be caught on them when it expands towards its target position.In this way, the airbag support helps the airbag expand smoothly andquickly upon its deployment.

It is preferable that the airbag support be attached to the airbag.According to this construction, the expanding force of the airbagquickly acts on the airbag support, so that the airbag support quicklyexpands to cover the instrument panel.

Also, it is preferable that the airbag support include a temporarilyattached portion that is detached from the airbag upon deployment of theairbag. According to this construction, the temporarily attached portionis detached from the airbag due to the expanding force of the airbagupon its deployment, and at this time, the temporarily attached portionbecomes free and then expands with respect to the instrument panelquickly.

Also, it is preferable that the airbag support include an instrumentpanel side portion provided to one side of the airbag that is closer tothe instrument panel and an occupant side portion provided to the otherside of the airbag that is closer to the occupant. According to thisconstruction, the airbag support covers protrusions and indentationspresent in the occupant's side, as well as those present in theinstrument panel side so that the airbag can expand more smoothly.

In this case, the airbag support may include a cut-off portion at whichthe airbag support is split. According to this construction, the airbagsupport can be provided in an integrated form, namely as a singlecomponent. That is, upon deployment of the airbag, the airbag support issplit at the cut-off portion into the instrument panel side portion andthe occupant side portion due to the expanding force of the airbag, andthe released end portions of the instrument panel portion and theoccupant side portion then moves quickly.

It is also preferable that the instrument panel side portion and theoccupant side portion of the airbag support be temporarily attached toeach other, so that they are detached upon deployment of the airbag.According to this construction, upon deployment of the airbag, theinstrument side portion and the occupant side portion of the airbagsupport are detached from each other due to the expanding force of theairbag. According to this construction, the size of each portion can beeasily set so as to be suitable for its functional requirement.

Also, it is preferable that the instrument panel side portion and theoccupant side portion be arranged such that the instrument side portionwould expand before the occupant side portion upon deployment of theairbag. According to this construction, the instrument panel sideportion is made expand before the occupant side portion, which isadvantageous in a case where priority should be given to coveringprotrusions and indentations on the instrument panel.

Also, it is preferable that the airbag support include an expansionguide for guiding expansion of the airbag support. In this case, upondeployment of the airbag, the airbag support is guided by the expansionguide so that it stably expands in a preferred direction.

For example, the expansion guide may be formed by a guide stitch sewingthe airbag and airbag support together. At least one portion of theguide stitch extends along a direction the airbag support would expandupon deployment of the airbag. This construction is advantageous interms of cost.

The guide stitch can be automatically formed by manufacturing the airbagif one portion of a stitch made to form the airbag or sew a tether tothe airbag is used to form the guide stitch.

Also, the expansion guide may be formed by a reinforcement of the airbagsupport, at least one portion of which extending along a direction theairbag support would expand upon deployment of the airbag. Thereinforcement may be formed separated from the airbag support, andtherefore can be easily formed in a preferred shape, namely thereinforcing effect by the reinforcement can be flexibly set.

The reinforcement may be formed by a portion of the airbag support thatis sewn into a specific form or at which a stitch is made. In this case,the equipment for sewing the airbag can be utilized to produce thereinforcement, so that no additional equipment cost will therefore berequired. Also, the reinforcement may be formed by a portion of theairbag support on which sealing substance is applied. In this case, too,the equipment for applying sealing substance to the airbag can beutilized to produce the reinforcement, and therefore no additionalequipment cost will be required.

Meanwhile, it is preferable that the airbag support be a portion of acover for covering the opening of an airbag case in which the airbag isstored. This construction does not increase the number of necessaryparts and components, and is therefore advantageous in terms of cost.Also, it is preferable that the airbag support and the airbag beintegrally formed of a common base cloth. This construction also doesnot increase the number of necessary parts and components, and istherefore advantageous in terms of cost.

If the airbag support attached on the airbag is stored wrappedseparately from the airbag, it is possible to freely arrange the airbagsupport so that it would take a desired expanding behavior upondeployment of the airbag, independent of the expanding behavior of theairbag.

Also, it is preferable that the airbag support be attached at its bottomportion to the airbag, and the airbag support and the airbag be storedwith the top portion of the airbag support being separately fold fromthe airbag. In this case, the top portion of the airbag support wouldexpand, upon deployment of the airbag, without being restricted by theairbag, and therefore the airbag support expands before the airbag.

Also, it is preferable that an airbag case be provided, and the airbagand the airbag support be wrapped separately from each other and storedin the airbag case in such a way that the airbag support covers theairbag in the same case. With this arrangement, the airbag support holdsthe airbag, thus reducing the chances of the airbag being displaced ordeformed.

Also, it is preferable that an airbag case for storing the airbag beprovided, and the instrument side portion and the occupant side portionof the airbag support be wrapped separately and stored within the airbagcase together with the airbag in such a way that, in the same case, theairbag wrapped is covered by the occupant side portion and the occupantside portion is covered by the instrument panel side portion. Accordingto this construction, the airbag is supported by the support of theinstrument panel side portion and the occupant side portion, reducingthe chances of the airbag being displaced or deformed. Also, upondeployment of the airbag, the instrument panel side portion expandsbefore the occupant side portion.

Also, it is preferable that one end portion of the airbag support befree and an anchor portion be provided at the same end. According tothis construction, the expanding force of the airbag acts on the anchorportion so that the airbag support quickly expands with respect to theinstrument panel. The anchor portion, for example, may be formed byapplying sealing substance to the airbag support. In this case, theequipment for applying sealing substance to the airbag can be utilizedto provide the anchor portion, and no additional equipment cost willtherefore be required. Alternatively, the anchor portion may be formedby sewing one portion of the airbag support into a specific form. Inthis case, similarly, the equipment for sewing the airbag can beutilized to provide the anchor portion, and therefore no additionalequipment cost will be required.

Also, it is preferable that the airbag support be provided with afriction reducer for reducing friction between the airbag support andthe airbag. The friction reducer is provided to minimize or reduce thechances that the airbag support would get caught on the airbag upondeployment of the airbag. For example, the friction reducer may beformed by applying sealing substance to one side of the airbag supportcloser to the airbag. In this case, due to the sealing substanceapplied, the relative movements of the airbag and the airbag support canbe made smoother. In this case, namely, the sealing substance can beutilized to reduce the friction between the airbag and the airbagsupport.

Also, it is preferable that the friction reducer be formed by a portionof the airbag support that is folded onto another portion (overlappedportions) of the airbag support. Due to the thus folded portion of theairbag support, the relative movements of the airbag and the airbagsupport are made smooth, and therefore the airbag support can smoothlyexpand with respect to the instrument panel. Also, the friction reducermay be formed through an arrangement of the airbag support and theairbag where a weave direction of base cloth of the airbag and a weavedirection of base cloth of the airbag support are different Thisarrangement can be easily accomplished by appropriately setting thedirection of cutting out the airbag support from its base cloth.

Also, it is preferable that the airbag support be attached at the bottomportion to the airbag while the top portion is free, and a peripherallength of a top side of the airbag support be longer than a peripherallength of a bottom side of the airbag support. According to thisconstruction, even if there is a protrusion such as a steering column ata position corresponding to the top portion, the airbag support canappropriately expand while avoiding the protrusion.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and/or further objects, features and advantages of theinvention will become more apparent from the following description ofpreferred embodiments with reference to the accompanying drawings, inwhich like numerals are used to represent like elements and wherein:

FIG. 1 is a side view schematically showing a knee protection apparatusin accordance with one embodiment of the present invention;

FIG. 2 is a perspective view showing the configuration of a knee airbagmodule, a panel, brackets, and an instrument panel reinforcement;

FIG. 3 is an sectional side view showing the knee airbag module shown inFIG. 1;

FIG. 4 is another side view schematically showing the knee protectionapparatus shown in FIG. 1 when the airbag is deploying;

FIG. 5 is another side view schematically showing the knee protectionapparatus when the deployment of the airbag has been completed;

FIG. 6 is a sectional side view schematically illustrating one examplewhere the airbag support is provided to both the instrument panel sideand the occupant side of the airbag;

FIG. 7 is a perspective view showing the airbag and the airbag supportof FIG. 6 as viewed from the rear side of the vehicle;

FIG. 8 is a sectional side view schematically illustrating one examplewhere one end portion of the airbag support is temporarily fixed to theairbag using a double-daces tape;

FIG. 9 is a sectional side view schematically illustrating one examplewhere a cut-off line is provided at an intermediate portion of theairbag support;

FIG. 10 is a perspective view showing the airbag and the airbag supportof FIG. 9 as viewed from the occupant's side;

FIG. 11 is a sectional side view schematically illustrating one examplewhere the instrument panel side portion and the occupant side portion ofthe airbag support are temporarily fixed to each other usingdouble-sided tape;

FIG. 12 is a sectional side view schematically illustrating one examplewhere the instrument panel side portion and the occupant side portion ofthe airbag support are sewn and thus temporarily fixed to each other;

FIG. 13 is a sectional side view illustrating a case where the airbagsupport of FIG. 12 has expanded;

FIG. 14 is a sectional side view schematically illustrating one examplewhere the instrument panel side portion and the occupant side portion ofthe airbag support are arranged such that the instrument panel sideportion would expand before the occupant side portion upon deployment ofthe airbag;

FIG. 15 is a sectional side view schematically illustrating one examplewhere the airbag is first wrapped and stored into the airbag case, afterwhich the instrument panel side portion and the occupant side portion ofthe airbag support are sequentially wound and stored into the same case;

FIG. 16 is a sectional side view schematically illustrating one examplewhere the airbag is first wrapped and stored into the airbag case, afterwhich instrument panel side portion and the occupant side portion of theairbag support are folded like “bellows” and sequentially stored intothe same case;

FIG. 17 is a sectional side view schematically illustrating one examplewhere the airbag support including the instrument panel side portion andthe occupant side portion and the airbag are integrally formed of acommon base cloth;

FIG. 18 is a view schematically illustrating one example where theexpansion guide is formed by a stitch sewing the airbag and the airbagsupport together;

FIG. 19 is a view schematically illustrating one example where theexpansion guide is formed by a stitch sewing the airbag and the airbagsupport together;

FIG. 20 is a view schematically illustrating one example where theexpansion guide is formed by a stitch sewing the airbag and the airbagsupport together;

FIG. 21 is a view schematically illustrating one example where theexpansion guide is formed by a stitch sewing the airbag and the airbagsupport together;

FIG. 22 is a view schematically illustrating one example where theexpansion guide is formed by a portion of a stitch made to from theairbag;

FIG. 23 is a view schematically illustrating one example where theexpansion guide if formed by a portion of a stitch sewing a tether tothe airbag;

FIG. 24 is a view schematically illustrating one example where anadhered potion of the airbag support through which the airbag support isattached to the airbag is formed using adhesive such that at least oneportion of the adhered portion extends along a direction the airbagsupport would expand upon deployment of the airbag;

FIG. 25 is a view schematically illustrating another example where theadhered potion is formed;

FIG. 26 is a view schematically illustrating another example where theadhered potion is formed;

FIG. 27 is a view schematically illustrating another example where theadhered potion is formed;

FIG. 28 is a view schematically illustrating one example where areinforcement is formed by a portion of the airbag support sewn into aspecific form;

FIG. 29 is a view schematically illustrating another example where thereinforcement is formed by a portion of the airbag support sewn into aspecific form;

FIG. 30 is a view schematically illustrating another example where thereinforcement is formed by a portion of the airbag support sewn into aspecific form;

FIG. 31 is a view schematically illustrating one example where thereinforcement is formed by a portion of the airbag support at which astitch is made;

FIG. 32 is a view schematically illustrating one example where thereinforcement is formed by a portion of the airbag support on whichsealing substance is applied;

FIG. 33 is a view schematically illustrating another example where thereinforcement is formed by a portion of the airbag support on whichsealing substance is applied;

FIG. 34 is a sectional side view schematically illustrating one examplewhere the airbag support is formed as one portion of the airbag cover;

FIG. 35 is a sectional side view showing a case where the airbag shownin FIG. 34 has been deployed;

FIG. 36 is a sectional side view schematically illustrating one examplewhere the airbag support and the airbag are integrally formed of acommon base cloth;

FIG. 37 is a sectional side view schematically illustrating one examplewhere the airbag and the airbag support are wrapped separately andstored within the airbag case;

FIG. 38 is a sectional side view schematically illustrating anotherexample where the airbag and the airbag support are wrapped separatelyand stored within the airbag case;

FIG. 39 is a sectional side view schematically illustrating one examplewhere the airbag support is attached at the bottom portion to theairbag, and the airbag support and the airbag are stored with the topportion of the airbag support separately wrapped from the airbag;

FIG. 40 is a sectional side view schematically illustrating one examplewhere the airbag support is attached at the bottom portion to theairbag, and the airbag support and the airbag are stored with the topportion of the airbag support separately wrapped (folded) from theairbag;

FIG. 41 is a view schematically illustrating one example where an anchorportion is formed by the top portion of the airbag support that has beenfolded twice and sewn to the airbag support;

FIG. 42 is a view schematically illustrating one example where theanchor portion is formed by the top portion folded once and sewn to theairbag support so as to form a loop and a bar provided in that loop;

FIG. 43 is a view schematically illustrating one example where theanchor portion is formed by the top portion on which sealing substanceis thinly applied;

FIG. 44 is a view schematically illustrating one example where theanchor portion is formed by the top portion of the airbag support wherethe sealing substance is additionally applied onto a thin layer of thesame substance that has already been created throughout the entiresurface of the airbag support;

FIG. 45 is a view schematically illustrating one example where theanchor portion is formed by the top portion of the airbag support onwhich the sealing substance is thickly applied;

FIG. 46 is a view schematically illustrating one example where theanchor portion is formed by the top portion of the airbag support onwhich two stitches have been made;

FIG. 47 is a sectional side view schematically illustrating one examplewhere a friction reducer is formed by a layer of sealing substancecreated on one side of the airbag support closer to the airbag;

FIG. 48 is a sectional side view schematically illustrating one examplewhere the friction reducer is formed by overlapped portions of theairbag support;

FIG. 49 is a sectional side view schematically illustrating anotherexample where the friction reducer is formed by overlapped portions ofthe airbag support;

FIG. 50 is a view schematically illustrating one example where thefriction reducer is formed through an arrangement of the airbag supportand the airbag where a weave direction of base cloth of the airbag and aweave direction of base cloth of the airbag support are different;

FIG. 51 is a view schematically illustrating one example where theperipheral length of the top side of the airbag support is made longerthan the bottom side of the airbag support by forming a half-round notchsubstantially at the center of the same top side;

FIG. 52 is a view schematically illustrating one example where theperipheral length of the top side of the airbag support is made longerthan the bottom side of the airbag support by forming a V-shaped notchsubstantially at the center of the same top side;

FIG. 53 is a view schematically illustrating one example where theperipheral length of the top side of the airbag support is made longerthan the bottom side of the airbag support by forming a slit notchsubstantially at the center of the same top side;

FIG. 54 is a view schematically showing a state where the airbag supportof FIG. 53, as viewed from the opposite side, has expanded;

FIG. 55 is a view schematically illustrating one example where theperipheral length of the top side of the airbag support is made longerthan the bottom side of the airbag support by forming the airbag supportin a trapezoidal shape;

FIG. 56 is a view schematically showing a state where the airbag supportof FIG. 55, as viewed from the opposite side, has expanded;

FIG. 57 is a view schematically illustrating one example where theperipheral length of the top side of the airbag support is made longerthan the bottom side of the airbag support by providing a portion of theairbag support folded in a fan-like shape;

FIG. 58 is a view schematically illustrating another example where theperipheral length of the top side of the airbag support is made longerthan the bottom side of the airbag support by providing a portion of theairbag support folded in a fan-like shape;

FIG. 59 is a view schematically illustrating another example where theperipheral length of the top side of the airbag support is made longerthan the bottom side of the airbag support by providing a portion of theairbag support folded in a fan-like shape;

FIG. 60 is a sectional side view schematically illustrating one examplewhere the peripheral length of the top side of one portion of the airbagsupport is made longer than the top side of another portion of theairbag support when the airbag support has been split at a cut-offportion into those portions;

FIG. 61 is a back view showing the airbag support and the airbag in FIG.60;

FIG. 62 is a sectional side view schematically illustrating anotherexample where the peripheral length of the top side of one portion ofthe airbag support is made longer than the top side of another portionof the airbag support when the airbag support has been split at acut-off portion into those portions; and

FIG. 63 is a back view showing the airbag support and the airbag in FIG.62.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, exemplary embodiments of the present invention will bedescribed with reference to the accompanying drawings. FIGS. 1 to 5 areviews schematically showing the configuration of a knee protectionapparatus for a vehicle occupant in accordance with one embodiment ofthe invention. According to this embodiment, a knee airbag module 10 isfixed, at substantially the same height as knees B of an occupant A, toan instrument panel reinforcement 23 via a panel 21 and right and leftbrackets 22, and to a bottom portion 24A of an instrument panel 24 viathe panel 21.

The knee airbag module 10 thus located in front of the knees B of theoccupant A, includes an airbag 11, an inflator 12 for supplying gas tothe airbag 11 upon collision of the vehicle, an airbag case 13 forstoring the airbag 11 and the inflator 12, and an airbag cover 14covering a rear opening 13 a of the airbag case 13 (see FIG. 3).

The airbag 11 is formed of woven cloth (i.e., base cloth) sewn into awide rectangular shape as viewed from the occupant side. The airbag 11thus formed is then wrapped and stored into the airbag case 13 as shownin FIGS. 1, 3. When deployed, the airbag 11 is ejected from the airbagcase 13 and develops towards the rear side of the vehicle, and thenupward thus expanding between the instrument panel 24 and the knees B ofthe occupant A to protect the same knees. Also, sealing substance (e.g.,silicon) is applied to the surface of the airbag 11 to improve theairtightness.

The inflator 12, installed within the airbag case 13 together with theairbag 11, is used to supply gas into the airbag 11 upon collision ofthe vehicle. The airbag case 13 has a rectangular shape and is made ofmetal plates. In the rear side of the airbag case 13 is formed the rearopening 13 a facing toward the rear side of the vehicle, and the airbagcase 13 is attached to the panel 21 in such a way that the rear opening13 a and an opening 21A formed in the lower portion of the panel 21 arealigned.

The airbag cover 14 is a resin-made cover having a wide rectangularshape as viewed from the occupant's side, and is attached to the airbagcase 13 and the panel 21 so as to cover the rear opening 13 a of theairbag case 13 and the opening 21 a of the panel 21. The airbag cover 14includes a door portion 14 a having a wide rectangular shape andprovided in a position corresponding to the rear opening 13 a of theairbag case 13 and the panel 21 a of the panel 21. Also, a cut-off line14 b of small thickness is formed along the upper, left, and right edgesof the door portion 14 a, and a hinge portion 14 c of relatively smallthickness is formed along the lower edge of the door portion 14 a, sothat the door portion 14 a opens downward upon deployment of the airbag11.

The panel 21 is a thin plate plastically deformable to absorb stress.Referring to FIG. 2, the panel 21 is attached at upper mount portions 21b to the rear end portions of the brackets 22, and at a lower mountportion 21 c to the lower end portion of the instrument panel 24. Also,beads 21 d (i.e., reinforcement portions) extending substantially in thevertical direction are formed in the right and left sides of the panel21, respectively.

Each bracket 22 is made of a relatively thick plate plasticallydeformable to absorb stress. Referring to FIGS. 1, 2, each bracket 22 isfixed at a tip 22 a to the panel 21 and includes two bent portionsbending downward.

Furthermore, the knee protection apparatus of this embodiment includesan airbag support 15 attached to a specific portion of the airbag 11.The airbag support 15 is made of woven cloth of the same kind as theairbag 11 and has an elongated shape. More specifically, the airbagsupport 15 is attached at its bottom portion 15 a to the airbag 11, andis stored wrapped within the airbag case 13 together with the airbag 11.For example, the airbag support 15 may be sewn to the airbag 11, or maybe bonded to the airbag using adhesive (e.g., thermal adhesive).

Referring to FIGS. 4, 5, when the airbag 11 is deployed by the gassupplied from the inflator 12, the airbag support 15 expands in such away that a top portion 15 b (i.e., free end portion) of the airbagsupport 15 moves upward so that the airbag support 15 covers protrusionsand indentations on the instrument panel 24, helping the airbag 11smoothly expand during its deployment. Thus, the airbag support 15reduces the chances of the airbag 11 being caught on such protrusionsand indentations on the instrument panel 24, thereby assuring quickdeployment of the airbag 11.

Also, since the airbag support 15 is attached to the airbag 11, upondeployment of the airbag 11, the expanding force of the airbag 11quickly acts on the airbag support 15 and the airbag support 15 quicklycover the instrument panel 24.

According to the foregoing construction, the airbag support 15 isarranged to expand with respect to the instrument panel side of theairbag 11. However, referring to FIGS. 6, 7, the airbag support 15 mayalternatively be arranged such that the bottom portion 15 a of theairbag support 15 expands with respect to the instrument panel side ofthe airbag 11 and the top portion 15 b expands with respect to theoccupant side of the airbag 11, respectively. In this case, as well asprotrusions and indentations on the instrument panel 24, those presentin the occupant side of the airbag 11 are covered by the airbag support15, which reduces the chances of the airbag 11 being caught on themduring deployment of the airbag 11.

While the top portion 15 b (i.e., free end portion) of the airbagsupport 15 is not fixed to the airbag 11 in the examples of FIGS. 1 to5, it may temporarily be fixed to the airbag 11 using a double-sidedtape 16, or the like (See FIG. 8). In this case, upon deployment of theairbag 11, the top portion 15 b is detached from the airbag 11 as theairbag support 15 expands by the expanding force of the airbag 11, andthe detached top portion 15 b then quickly moves towards the instrumentpanel 24.

FIGS. 9, 10 show examples where the top portion 15 b is sewn to theairbag 11 and a cut-off line 15 c is provided at an intermediate portionof the airbag support 15.

In this case, upon deployment of the airbag 11, the airbag support 15,receiving the expanding force of the airbag 11, is split at the cut-offline 15 c into an instrument panel side portion 15A and an occupant sideportion 15B, and the top portion of each portion then quickly moves.

According to this construction, the two separate portions 15A, 15B areprovided in an integrated form and attached to the airbag 11. In theexample of FIG. 9, a tether 11 a is sewn and thus fixed to the inside ofthe airbag, and the thread sewing the tether 11 a to the airbag 11 isutilized to sew the airbag support 15 to the airbag 11.

While the airbag support 15, in the above examples, is provided in anintegrated form and is split at the cut-off line 15 c into theinstrument panel side portion 15A and the occupant side portion 15B upondeployment of the airbag 11, these portions may be provided separated,as in the examples shown in FIGS. 11, 12.

Referring to FIG. 11, the instrument panel side portion 15A and theoccupant side portion 15B are temporally fixed to each other via adouble-sided tape 16, such that the bottom portion 15 a would expandbefore the free end portion 15 b upon deployment of the airbag 11.

Meanwhile, referring to FIG. 12, the instrument panel side portion 15Aand the occupant side portion 15B are sewn and thus temporarily fixed toeach other, such that the instrument panel side portion 15A would expandbefore the occupant side portion 15B upon deployment of the airbag 11.

According to these constructions, the temporarily fixed instrument panelside portion 15A and occupant side portion 15B are separated due to theexpanding force of the airbag 11 upon its deployment as shown in FIG.13, and at this time the instrument panel side portion 15A expandsbefore the occupant side portion 15B. Such an arrangement, inparticular, is effective in a case where priority should rather be givento covering protrusions and indentations on the instrument panel 24,than covering those present in the occupant side.

FIG. 14 shows one example where the instrument panel side portion 15Aand the occupant side portion 15B are arranged such that the instrumentpanel side portion 15A would expand before the occupant side portion 15Bupon deployment of the airbag 11. In this example, the airbag 11, theinstrument panel side portion 15A, and the occupant side portion 15B arearranged before stored into the airbag case 13, such that the wrappedtop portion of the occupant side portion 15B is placed on the top of theairbag 11 and the wrapped top portion of the instrument panel sideportion 15A is placed on the top portion of the occupant side portion15B.

In the examples of FIGS. 11, 12, 14, the instrument panel side portion15A, the occupant side portion 15B and the airbag 11 are substantiallytogether wrapped and stored into the airbag case 13. In the examplesshown in FIGS. 15, 16, however, the airbag 11 is first wrapped or foldedlike “bellows” and stored into the airbag case 13, and then theinstrument panel side portion 15A and the occupant side portion 15B arewrapped and stored into the airbag case 13.

Also, the instrument panel side portion 15A and the occupant sideportion 15B are formed separated from the airbag 11 in the aboveexamples. In view of this, FIG. 17 shows one example where theseportions and the airbag 11 are integrally formed of a common base cloth.This construction does not increase the number of necessary parts. andis therefore advantageous in terms of cost.

Also, in the examples shown in FIGS. 11 to 17, the instrument panel sideportion 15A and the occupant side portion 15B are formed independent,and their end portions (i.e., top portions) can be overlapped.Therefore, it is possible to set a preferred size of each portion inaccordance with functional requirements thereof.

In the examples of FIGS. 15, 16, the instrument panel side portion 15Aand the occupant side portion 15B, separately wrapped from each otherand from the airbag 11, are stored within the airbag case 13 in such away that the occupant side portion 15B is placed on the top the airbag11 and the instrument panel side portion 15A is placed on the top of theoccupant side portion 15B.

In this case, the airbag 11 is supported by the instrument panel sideportion 15A and the occupant side portion 15B, which reduces the chancesof the airbag 11 being displaced or deformed. Also, the instrument panelside portion 15A can be arranged so as to expand before the occupantside portion 15B upon deployment of the airbag 11, and the expandingbehavior of each portion can be set independent of the airbag 11.

Next, FIGS. 18 to 33 show examples where an expansion guide is provided,which guides the airbag support 15 so that it stably expands in apreferred direction.

In these examples, the expansion guide is formed by a fixing stitch thatis made of a thread 17 b strong enough to withstand stress appliedduring expansion of the airbag support 15, with respect to thelongitudinal direction of the vehicle (i.e., direction the airbagsupport 15 expands upon deployment of the airbag). In this case, aportion of a thread sewing the airbag support 15 to the airbag 11 may beused as the thread 17 b, which is advantageous in terms of cost.

For example, in the example of FIG. 22, a portion of the thread 11 bforms the fixing stitch extending along the direction the airbag support15 would expand upon deployment of the airbag 11. Similarly, in theexample of FIG. 23, a portion of the thread 11 c sewing the tether 11 cto the airbag 11 forms the fixing stitch. There are just examplesindicating the fixing stitch can easily be formed.

FIGS. 24 to 27 illustrate examples where the expansion guide is formedby an adhered portion of the airbag support 15 through which the airbagsupport 15 is attached to the airbag 11. The adhered potion is formedusing adhesive (e.g., thermal adhesive) 18 so that at least one portionof the adhered portion extends along the longitudinal direction of thevehicle (i.e., direction the airbag support 15 expands upon deploymentof the airbag). In this example, the adhesive applied to attach theairbag support 15 to the airbag 11 may be utilized to form the adheredportion, which is advantageous in terms of cost.

Other examples are shown in FIGS. 28 to 33, where the expansion guide isformed by a reinforcement C of the airbag support 15. Referring to thedrawings, the reinforcement C is provided independent of the airbag 11,and it is therefore possible to easily form the reinforcement C into adesired shape, and thus achieve improved flexibility in setting a targeteffect associated therewith.

In the examples of FIGS. 28 to 31, the reinforcement C is formed by asewn portion of the airbag support 15. In this case, the equipment forsewing the airbag 11 can be utilized to form the reinforcement C so thatno additional equipment cost will therefore be required. In the examplesof FIGS. 32, 33, the reinforcement C is formed by a portion of theairbag support 15 on which sealing substance 19 is applied to improvethe airtightness of that portion. In this case, too, the equipment forapplying sealing substance to the airbag 11 may be utilized to form thereinforcement C so that no additional equipment cost will therefore berequired.

Other examples are shown in FIGS. 34, 35 where the airbag support 15 isformed as one portion of an airbag cover 14 covering the opening 13 a ofthe airbag case 13 such that it will open to release the airbag 11 uponits deployment. This construction does not increase the number ofnecessary parts or components, and is therefore advantageous in terms ofcost. In one example shown in FIG. 36, the airbag support 15 and theairbag 11 are integrally formed of a common base cloth, which does notincrease the number of necessary parts or components and is thereforeadvantageous in terms of cost.

Other examples are shown in FIGS. 37, 38 where the airbag support 15attached to the airbag 11 is wrapped and stored within the airbag case13 separately from the airbag 11. In this case, the expanding behaviorof the airbag support 15 can be set independent of the airbag 11. Also,since the airbag support 15 is placed on the airbag 11 within the airbagcase 13, it reduces the chances of the airbag 11 being displaced ordeformed.

Other examples are shown in FIGS. 39, 40 where the airbag support 15 isadhered at the bottom portion 15 a to the airbag 11, and the top portion15 b is separately wrapped from the airbag 11 while other portion of theairbag support 15 is wrapped together with the airbag 11. In this case,the top portion 15 b, upon deployment of the airbag 11, is notrestricted by the airbag 11 and therefore quickly expands, and theexpansion of the airbag support 15 finishes before the deployment of theairbag 11.

Other examples are shown in FIGS. 41 to 46 where the top portion 15 b ofthe airbag support 15 is formed as a free end portion including ananchor portion D. In this case, upon deployment of the airbag 11, theexpanding force of the airbag 11 acts on the anchor portion D so thatthe airbag support 15 quickly expands with respect to the instrumentpanel 24.

In the example of FIG. 41, the anchor portion D is formed by the topportion 15 b folded twice and sewn to the airbag support 15. In FIG. 42,the anchor portion D is formed by the top portion 15 b folded once andsewn to the airbag support 15 so as to form a loop and a bar provided inthat loop. In the example of FIG. 46, the anchor portion D is formed bytwo stitches made at the top portion 15 b. According to these examples,the equipment for sewing the airbag 11 can be utilized to form theanchor portion D so that no additional equipment cost will therefore berequired.

In the example of FIG. 43, the anchor portion D is formed by the topportion 15 b on which sealing substance 19 is thinly applied. In theexample of FIG. 44, the anchor portion D is formed by the top portion 15b of the airbag support 15 where the sealing substance 19 isadditionally applied onto a thin layer of the same substance that hasalready been created throughout the entire surface of the airbag support15. According to these examples, the anchor portion D can be formedusing the same equipment as used to apply the sealant to the airbag,thus requiring no additional equipment cost.

Other examples are shown in FIGS. 47 to 50 where a friction reducer forreducing the friction between the airbag support 15 and the airbag 11 isprovided to minimize the chances of the airbag support 15 being caughtby the airbag 11 when the airbag support 15 expands upon deployment ofthe airbag 11. In the example of FIG. 47, the friction reducer is formedby a layer of sealing substance created between the airbag support 15and the airbag 11. More specifically, the sealing substance is thinlyapplied to the airbag support 15 so that the layer of sealing substanceis created between the airbag support 15 and the airbag 11. If thesealing substance is also applied to the airbag 11, the effect ofsmoothing the relative motions of the airbag 11 and the airbag support15 can be further improved. Thus, in this case, the sealing substancecan be utilized to reduce the friction between the airbag 11 and theairbag support 15.

Other examples are shown in FIGs. 48 and 49, where the friction reduceris formed by two or more separate portions of the airbag support 15 thatare overlapped or a portion of the airbag support 15 folded onto itself.With thus overlapped portions of the airbag support 15, the relativemotions of the airbag 11 and the airbag support 15 are made smooth sothat the airbag support 15 would smoothly and quickly expand withrespect to the instrument panel.

Another example is shown in FIG. 50 where the friction reducer is formedby an arrangement of the airbag support 15 and the airbag 11 where theirweave directions are different. This arrangement can be easilyaccomplished by appropriately setting the direction of cutting out theairbag support 15 from the base cloth, and a preferred effect ofreducing the friction may be achieved by setting that directionappropriately.

Other examples are shown in FIGS. 51 to 59 where the airbag support 15is attached at the bottom portion 15 a to the airbag 11 while the topportion 15 b is free, and the peripheral length of the top side of theairbag support 15 is longer than the bottom side of the airbag support15. In the example of FIG. 51 a half-round notch 15 b 1 is formedsubstantially at the center of the top side of the airbag support 15 sothat the peripheral length of the top side is longer than the bottomside of the airbag support 15. In the example of FIG. 52, likewise, aV-shaped notch 15 b 2 is formed substantially at the center of the topside of the airbag support 15 so that the peripheral length of the topside is longer than the bottom side of the airbag support 15.

In the example shown in FIGS. 53 and 54, a slit 15 b 3 of apredetermined length is made substantially at the center of the topportion 15 b. Referring to FIG. 54, the top portion 15 b of the airbagsupport 15, upon deployment of the airbag 11, opens at the slit 15 b 3when it contacts and is thus pressed by a protrusion, such as a steeringcolumn 30, so that the peripheral length of the top side becomes longerthan the bottom side of the airbag support 15 as indicated in FIG. 54.In the examples of FIGS. 55 and 56, the airbag support 15 is formedtrapezoidal so that the length of the top side of the airbag support 15is longer than the bottom side of the airbag support 15. In the examplesof FIGS. 57 and 58, the top portion 15 b of the airbag support 15 isformed like a “folding fan” so that the length of the top side of theairbag support 15 becomes longer than the bottom side when the airbagsupport 15 has expanded. In the example of FIG. 59, the airbag support15 is formed in a fan-like shape so that the length of top edge of theairbag support 15 is longer than the bottom side.

Other examples are shown in FIGS. 60 to 63 where a cut-off line 15 c isformed to split the airbag support 15 into two portions corresponding tothe instrument panel side and the occupant side of the airbag 11,respectively. The cut-off line 15 c is formed in such a shape that, whenthe airbag support has been split into such two portions, the peripherallength of the top side of one of the portions is longer than that of theother portion. For example, the center portion of the cut-off line 15cmay be formed in a V-shape as shown FIGS. 62 and 63.

According to the examples of FIGS. 51 to 59 where the length of the topside of the airbag support 15 is longer than its bottom side, and theexamples of FIGS. 60 to 63 where the top side of one of the two portionsof the airbag support 15 is longer than that of the other portion, theairbag support 15, even if there is a protrusion like the steeringcolumn 30, can smoothly expand by avoiding that protrusion.

1. A knee protection apparatus for an occupant of a vehicle, comprising:an airbag disposed in front of a knee of the occupant; an inflator forsupplying gas to the airbag upon collision of the vehicle so that theairbag is deployed by the supplied gas; and a non-inflatable airbagsupport that is directly attached to the airbag and is structured toexpand upon deployment of the airbag so as to provide a barrier betweenthe instrument panel and the airbag, wherein one end portion of theairbag support is free, the airbag support extends in such a way thatthe one end portion of the airbag support separates upward and movesupward above the airbag upon the deployment of the airbag, and the otherend portion of the airbag support is directly attached at the airbag,the other end portion being located in a lower side of the airbagsupport when the airbag has deployed.
 2. The knee protection apparatusaccording to claim 1, wherein the airbag support includes a temporarilyattached portion that is detached from the airbag upon the deployment ofthe airbag.
 3. The knee protection apparatus according to claim 1,wherein the airbag support includes an instrument panel side portionprovided to one side of the airbag that is closer to the instrumentpanel and an occupant side portion provided to the other side of theairbag that is closer to the occupant.
 4. The knee protection apparatusaccording to claim 3, wherein the airbag support includes a cut-offportion at which the airbag support is split upon the deployment of theairbag.
 5. The knee protection apparatus according to claim 3, whereinthe instrument panel side portion and the occupant side portion of theairbag support are temporarily attached to each other, so that they aredetached upon the deployment of the airbag.
 6. The knee protectionapparatus according to claim 3, wherein the instrument panel sideportion and the occupant side portion are arranged such that theinstrument side portion expands before the occupant side portion uponthe deployment of the airbag.
 7. The knee protection apparatus accordingto claim 3, further including an airbag case for storing the airbag,wherein the instrument side portion and the occupant side portion of theairbag support are wrapped separately and stored within the airbag casetogether with the airbag in such a way that the airbag wrapped iscovered by the occupant side portion and the occupant side portion iscovered by the instrument panel side portion.
 8. The knee protectionapparatus according claim 1, wherein the airbag support is provided withan expansion guide for guiding the airbag support to stably expand in apredetermined expanding direction.
 9. The knee protection apparatusaccording to claim 8, wherein the expansion guide is a guide stitchsewing the airbag support and the airbag together, at least one portionof the guide stitch extending along the predetermined expandingdirection.
 10. The knee protection apparatus according to claim 9,wherein the guide stitch is formed by a portion of a stitch made to formthe airbag.
 11. The knee protection apparatus according to claim 9,further comprising a tether, wherein the guide stitch is formed by aportion of a stitch sewing the tether to the airbag.
 12. The kneeprotection apparatus according to claim 8, wherein the expansion guideis formed by a reinforcement provided in the airbag support, at leastone portion of the reinforcement extending along the predeterminedexpanding direction.
 13. The knee protection apparatus according toclaim 12, wherein the reinforcement is formed by a portion of the airbagsupport that is sewn into a specific form or at which a stitch is made.14. The knee protection apparatus according to claim 12, wherein thereinforcement is formed by a portion of the airbag support on whichsealing substance is applied.
 15. The knee protection apparatusaccording to claim 1, wherein the airbag support and the airbag areintegrally formed of a common base cloth.
 16. The knee protectionapparatus according to claim 1, wherein the airbag support and theairbag are separately wrapped and stored.
 17. The knee protectionapparatus according to claim 1, the one end portion of the airbagsupport being a top portion another end portion of the airbag supportbeing a bottom portion, wherein the airbag support is attached at thebottom portion to the airbag, and the airbag support and the airbag arestored with the top portion of the airbag support being separatelywrapped from the airbag.
 18. The knee protection apparatus according toclaim 1, further comprising: an airbag case in which the airbag isstored and wrapped, wherein the airbag and the airbag support arewrapped separately and stored in the airbag case in such a way that theairbag support covers the airbag in the same airbag case.
 19. The kneeprotection apparatus according to claim 1, wherein an anchor portion isprovided at the one end portion.
 20. The knee protection apparatusaccording to claim 19, wherein the anchor portion is formed by a portionof the airbag support on which sealing substance is applied.
 21. Theknee protection apparatus according to claim 19, wherein the anchorportion is formed by a portion of the airbag support that is sewn into aspecific form or at which a stitch is made.
 22. The knee protectionapparatus according to claim 1, wherein the airbag support is providedwith a friction reducer for reducing friction between the airbag supportand the airbag.
 23. The knee protection apparatus according to claim 22,wherein the friction reducer is formed by a layer of sealing substancecreated on one side of the airbag support closer to the airbag.
 24. Theknee protection apparatus according to claim 22, wherein the frictionreducer is formed by overlapped portions of the airbag support.
 25. Theknee protection apparatus according to claim 22, wherein the frictionreducer is formed by an arrangement of the airbag support and the airbagin which a weave direction of base cloth of the airbag and a weavedirection of base cloth of the airbag support are different.
 26. Theknee protection apparatus according to claim 1, the one end portion ofthe airbag support being a top portion and another end portion being abottom portion, wherein the airbag support is attached at the bottomportion to the airbag while the top portion is free, and a peripherallength of a top side of the airbag support is longer than a peripherallength of a bottom side of the airbag support.
 27. A knee protectionapparatus for an occupant of a vehicle, comprising: an airbag disposedin front of a knee of the occupant; an inflator for supplying gas to theairbag upon collision of the vehicle so that the airbag is deployed bythe supplied gas; a non-inflatable airbag support that is structured toexpand upon deployment of the airbag so as to provide a barrier betweenthe instrument panel and the airbag; an airbag case, in which the airbagis stored and wrapped; and an airbag cover for covering an opening ofthe airbag case, wherein the airbag support and the airbag cover areintegrally formed and the airbag support is stored in the airbag case,wherein one end portion of the airbag support is free, the airbagsupport extends in such a way that the one end portion of the airbagsupport separates upward from the airbag and moves upward above theairbag upon the deployment of the airbag, and the other end portion ofthe airbag support is integrally formed at the airbag cover, the otherend portion being located in a lower side of the airbag support when theairbag has deployed.